Single pump cooling arrangment

ABSTRACT

A cooling arrangement having a first circuit and a second circuit in fluid communication of a coolant with each other. The cooling arrangement includes a pump configured to receive the coolant from the first circuit and the second circuit, and to re-circulate the coolant back to the first circuit and the second circuit. Further, the cooling arrangement includes an after-cooler disposed in the first circuit. A thermostat is provided in connection with the after-cooler to regulate a flow of the coolant supplied to the pump based on the temperature of the coolant from the after-cooler. Further, a bypass line is disposed in parallel to the thermostat in the first circuit. The bypass line is configured to provide a constant bleed of the coolant from the first circuit to the pump.

TECHNICAL FIELD

The present disclosure relates to a cooling arrangement for a marinepower system, and more particularly to the cooling arrangement using asingle pump.

BACKGROUND

Typically, a marine power system employs a cooling arrangement forcooling of an engine, disposed therein. It is desired that the coolingarrangement with various components, may have the components to work attheir operating temperature ranges for better performance. For thispurpose, the cooling arrangement may utilize a two-circuitconfiguration, that is, the cooling arrangement include two differentcircuits for circulation of the coolant, with various components dividedtherein. Such cooling arrangement generally employs two separate pumpsfor circulation of the coolant in each of the two circuits of thecooling arrangement.

US Patent Publication No. 6,314,921 discloses a cooling system for anengine. The cooling system includes a radiator, and an after-coolerconfigured for cooling engine charge air from a turbocharger. Further, apump is provided to supply the coolant from the radiator to the engine.A separate circuit after-cooling pump is provided to circulate thecoolant from the radiator to the after-cooler. The cooling systemfurther includes an after-cooler coolant line to provide a pathway forfluid communication between the after-cooler and the radiator. Anorifice is disposed in series in the after-cooler coolant line to limitthe fluid flow therethrough.

SUMMARY

In one aspect, the present disclosure provides a cooling arrangementhaving a first circuit and a second circuit. The first and the secondcircuits are in fluid communication of a coolant with each other. Thecooling arrangement includes an after-cooler provided in the firstcircuit. Further, the cooling arrangement includes a pump configured toreceive the coolant from the after-cooler in the first circuit and thesecond circuit. The pump is circulating the coolant back to the firstcircuit and the second circuit. A thermostat is disposed in connectionwith the after-cooler in the first circuit. The thermostat is configuredto regulate the flow of the coolant provided to the pump based on thetemperature of the coolant from the after-cooler. Further, a bypass lineis provided in the first circuit parallel to the thermostat to provide aconstant bleed of the coolant from the first circuit to the pump.

In another aspect, the present disclosure provides a marine power systemincluding an engine. The marine power system includes the coolingarrangement, configured to extract heat from the engine by the coolant.The cooling arrangement includes the after-cooler for cooling thecoolant to be supplied to the engine. The thermostat is provided inconnection with the after-cooler and configured to regulate the flow ofthe coolant based on the temperature of the coolant from theafter-cooler. Further, the bypass line is disposed in parallel to thethermostat to provide a constant bleed of the coolant from theafter-cooler to the engine. An orifice is disposed in the bypass line tocontrol the flow of the coolant through the bypass line.

In yet another aspect, the present disclosure provides a method forcooling the engine. The method includes receiving the coolant from theengine to the pump. The coolant from the pump is pumped to theafter-cooler. The method further includes regulating the flow of thecoolant from the after-cooler to the pump, to be supplied back to theengine, by the thermostat. Finally, the method involves providing thebypass line in parallel to the thermostat to provide the constant bleedof the coolant from the after-cooler to the engine.

Other features and aspects of this disclosure will be apparent from thefollowing description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a schematic of a marine power system, according to anembodiment of the present disclosure; and

FIG. 2 illustrates a process flow diagram depicting various stepsinvolved in cooling an engine.

DETAILED DESCRIPTION

The present disclosure will now be described in detail with referencebeing made to accompanying figures. A marine power system 100 in whichdisclosed embodiments may be implemented is schematically illustrated inFIG. 1. The marine power system 100 of the present disclosure may beemployed to power various components of a machine, such as marine ships,recreational boats, or the like. The marine power system 100 may includean engine 102 to generate electric power (via a generator) for drivingvarious components of the marine power system 100. In an embodiment, theengine 102 may be a combustion engine, such as, a gasoline, diesel ornatural gas engine, etc.

The engine 102 may include an engine block 104, in which the combustionof fuel takes place. Further, the engine 102 may include an enginemanifold 106, which may be in contact or partially enclose the engineblock 104. The engine manifold 106 may receive and supply the fuel fromsome source, like a fuel tank, to the engine block 104. Further,according to an embodiment of the present disclosure, the enginemanifold 106 may also be configured for receiving a coolant in themarine power system 100.

The marine power system 100 of the present disclosure includes a coolingarrangement 108. The cooling arrangement 108 may provide a flow of thecoolant to extract heat, to be dissipated, from various components ofthe marine power system 100, and particularly the engine 102. In anembodiment, the coolant used in the cooling arrangement 108 may be anyone of treated water; water mixed with mineral oils, silicone oils,cutting fluids and/or anti-freeze like ethylene glycol, di-ethyleneglycol, etc.

In an embodiment, the cooling arrangement 108 may provide two circuits,namely, a first circuit 110 and a second circuit 112. In the exemplaryconfiguration, the first circuit 110 may be working at a hightemperature range, and the second circuit 112 at a low temperature rangein the cooling arrangement 108. For the purpose of the presentdisclosure, In FIG. 1, the cooling arrangement 108 is illustrated withlines required only for the flow of the coolant. However, it may becontemplated that the cooling arrangement 108 may include additionallines, such as, for example, for the flow of charge air, sea-water, etc.

Further, the cooling arrangement 108 may include a pump 114, in fluidcommunication with the first and the second circuits 110, 112. In anembodiment, the pump 114 may be any type of a positive displacementpump, such as, a centrifugal pump having a construction well known inthe art. The pump 114 may be configured to provide a pressure head forcirculation of the coolant between the first circuit 110 and the secondcircuit 112, in the cooling arrangement 108.

The pump 114 may receive the coolant from the first and the secondcircuits 110, 112, of the cooling arrangement 108. Subsequently, thepump 114 may provide the pressure head to circulate the coolant back tothe first and the second circuits 110, 112. In an embodiment, thecoolant from the first and second circuits 110, 112 may mix within thepump 114, before being re-circulated back in the cooling arrangement108.

In the marine power system 100, the coolant may be received by theengine 102, which is in connection with the second circuit 112 of thecooling arrangement 108. Specifically, the coolant may be received bythe engine manifold 106 in the engine 102. The engine manifold 106 beingin contact with the walls of the engine block 104, may extract the heatgenerated in the engine block 104 by the coolant, and supply the coolantback to the cooling arrangement 108 to dissipate the extracted heat.

Further, the cooling arrangement 108 may include a heat exchanger 116disposed in the second circuit 112 of the cooling arrangement 108. Theheat exchanger 116 may be disposed in connection with the engine 102 ofthe marine power system 100. In an embodiment, the heat exchanger 116may be a jacket-water heat exchanger using sea-water for extracting heatgained by the coolant from the engine 102.

The cooling arrangement 108 may also include various other components,supporting the operation of the engine 102 in the marine power system100. As illustrated, the cooling arrangement 108 may include an engineoil-cooler 118 and a turbocharger 120 disposed in the second circuit112. The engine oil-cooler 118 may be utilized to cool the engine oilfor the engine 102, by the coolant received from the pump 114.Similarly, the turbocharger 120 may be utilized to charge the air, forcombustion of fuel, intake in the engine 102.

Further, in an embodiment, the cooling arrangement 108 may include anafter-cooler 122 to cool the charge air, reducing an intake manifold airtemperature for the engine 102. This may be required for better fueleconomy and low emissions by the engine 102 in the marine power system100. The after-cooler 122 may receive the charge air, from theturbocharger 120 via a line (not illustrated), and extract heat from thecharge air by the coolant received from the pump 114. Subsequently, thecooled charge air may be supplied to the engine 102 in the marine powersystem 100.

For achieving better performance, the after-cooler 122 may be disposedin the first circuit 110, being the low temperature circuit, of thecooling arrangement 108. Further, in an embodiment, the coolingarrangement 108 may also include an after-cooler heat exchanger 124,disposed in connection with the after-cooler 122 in the first circuit110. The after-cooler heat exchanger 124 may be configured to furthercool the coolant supplied by the pump 114, from the first and the secondcircuit 110, 112, before being passed to the after-cooler 122 forcooling of the charge air.

In order to regulate the flow of the coolant, the cooling arrangement108 may also include one or more thermostats disposed therein. Inparticular, the cooling arrangement 108 may include a thermostat 126disposed in connection with the after-cooler 122. The thermostat 126 isconfigured to regulate the flow of the coolant from the first circuit110 to the pump 114 based on the temperature of the coolant from theafter-cooler 112. Specifically, the thermostat 126 may be configured toallow the coolant to flow to the pump 114 above a predeterminedtemperature limit.

In an embodiment, the cooling arrangement 108 may employ a triplethermostat configuration, that is, the cooling arrangement 108 includesthree thermostats working in combination to regulate the flow of thecoolant. In such a configuration, in addition to the thermostat 126, afirst auxiliary thermostat 128 and a second auxiliary thermostat 130 maybe provided in the first circuit 110 and the second circuit 112 of thecooling arrangement 108, respectively. For the purpose of the presentdisclosure, the thermostats 126, 128, 130 may be mechanically actuatedthermostats, for example, a thermostatic radiator valve, a pneumaticthermostatic valve, or the like.

Specifically, the first auxiliary thermostat 128 may be disposed betweenthe after-cooler heat exchanger 124 and the after-cooler 122 in thefirst circuit 110. The first auxiliary thermostat 128 may regulate theflow of the coolant from the pump 114 to the after-cooler 122, eithervia or bypassing the after-cooler heat exchanger 124. Similarly, thesecond auxiliary thermostat 130 may be provided between the heatexchanger 116 and the pump 114 in the second circuit 112. The secondauxiliary thermostat 130 may regulate the flow of the coolant from theengine 102 to the pump 114, either via or bypassing the heat exchanger116.

Further, the cooling arrangement 108 may include a bypass line 132disposed in parallel to the thermostat 126. Specifically, the bypassline 132 may be extending from the line between the after-cooler 122 andthe thermostat 126, to the line between the thermostat 126 and the pump114. The bypass line 132 may enable the cooling arrangement 108 to routethe flow of the coolant from the after-cooler 122 directly to the pump114, bypassing the thermostat 126, and thus provides a constant bleed ofthe coolant in the cooling arrangement 108.

In an embodiment, the bypass line 132 may include an orifice 134disposed within. The orifice 134 may be configured to control the flowof the coolant through the bypass line 132 in the cooling arrangement108. In an embodiment, the flow of the coolant through the bypass line132 may be dependent on the diameter of the orifice 134. In anembodiment, the diameter of the bypass line 132 may be in the range fromabout 2 to 12 millimeters. In an exemplary configuration, the diameterof the bypass line 132 is about 5 millimeters.

According to an alternative embodiment of the present disclosure, thebypass line 132, instead of being a separate line, may be formed withinin the thermostat 126. That is, the bypass line 132 may be defined as analternative path for the flow of the coolant in the thermostat 126, inaddition to the regular path which allows the flow of the coolanttherethrough based on the regulation on the basis of temperature.Therefore, in such a configuration, this additional path may function asthe bypass line 132 with the orifice 134 disposed therein, and providesa controlled constant bleed of the coolant for the engine 102 in thecooling arrangement 108.

INDUSTRIAL APPLICABILITY

In operation, the engine 102 in the marine power system 100 may generateheat in the engine block 104 due to the combustion of the fuel. Thegenerated heat may need to be dissipated for proper working of theengine 102 in the marine power system 100. Therefore, it is desired thatthe marine power system 100 may be provided with the cooling arrangement108. The cooling arrangement 108 may supply the coolant to the engine102 and extract heat in the process. Specifically, the coolingarrangement 108 may supply the coolant to the engine manifold 106, andextract heat generated from the engine block 104 in the engine 102.Further, the cooling arrangement 108 may dissipate the heat usingvarious components working in combination.

It has been observed that for the efficient working of the coolingarrangement 108, various components may be disposed such as thecomponents operate within the specified operating temperature ranges.For this purpose, the cooling arrangement 108 may be provided with twocircuits, the first circuit 110 working at a high temperature range andthe second circuit 112 working at a low temperature range. Conventionalcooling arrangements utilizing such two-circuit configuration, typicallyemploys two separate pumps, for each of the two circuits.

The present disclosure provides the cooling arrangement 108 for themarine power system 100, utilizing two-circuit configuration byemploying only the single pump 114. This is made possible because thecooling arrangement 108 utilizes the triple-thermostat configuration,that is, the thermostats 126, 128, 130 working in conjunction with eachother. The triple-thermostat configuration provides for betterregulation of flow of the coolant based on the temperature and thereforeallows for using a single pump 114 in the process.

The present disclosure also provides a method for cooling the engine 102employing the cooling arrangement 108 with the single pump 114. FIG. 2illustrates a process flow diagram 200 depicting various steps performedsequentially to achieve the purpose.

As illustrated, in step 202, the coolant from the engine 102 is receivedin the pump 114. This coolant, from the engine 102 via the secondcircuit 112, may mix with the coolant from the first circuit 110 of thecooling arrangement 108. Further, in step 204, the coolant from the pump114 is supplied to the after-cooler 122, in the first circuit 110. Asthe coolant passes through the after-cooler 122, the temperature of thecoolant may rise due to the gained heat, from cooling the charge air.

In certain cases, the temperature of the coolant, after passing throughthe after-cooler 122 in the first circuit 110, may still be at asubstantially lower temperature to be supplied to the second circuit 112for cooling of the engine 102 at a low load condition, that is, when theengine 102 is generating low heat in the second circuit 112.

Therefore, in step 206, the flow of the coolant back from theafter-cooler 122 to the pump 114 is regulated via the thermostat 126.The thermostat 126 ensures that the temperature of the coolant flowingto the pump 114, to be supplied to the engine 102 after mixing in thepump 114, may be above a certain predetermined temperature to avoidovercooling of the engine 102.

As the load of the engine 102 is increased, the flow of the coolant mayneed to be increased. In such a situation, the thermostat 126 may not beable to instantaneously provide the required flow rate because of finiteresponse time. So, as in step 208, the bypass line 132 is provided toroute the coolant from the after-cooler 122 to the engine 102, via thepump 114.

The cooling arrangement 108 with the bypass line 132 ensures a constantbleed in order to provide flow of the coolant to the engine 102 at alltimes. This may be put in place to compensate for transient loading,that is, the sudden variation of load in the engine 102. The bypass line132 may act to compensate for the finite response time of the thermostat126 by allowing at least some flow of the coolant to the engine 102 inthe second circuit 112.

Further, the cooling arrangement 108 may further be able to cope withvarying cooling requirements of the marine power system 100 by relativepositioning and combined operation of the thermostats 126, 128, 130 inthe cooling arrangement 108. The thermostat 126 may ensure that thecoolant supplied from the after-cooler 122 to the pump 114 is above aminimum predetermined temperature. Thus, the thermostat 126 may preventthe flow of the coolant at a low ambient temperature from the firstcircuit 110 to return to the second circuit 112 for the engine 102 inthe low load condition. Also, the thermostat 126 may limit the exposureto overcooling for the components in the first circuit 110, especiallythe engine 102 and reduces the risk of the damage to the engine 102 inthe marine power system 100.

Additionally, the first auxiliary thermostat 128 may ensure that thecoolant supplied from the pump 114 to the after-cooler 122 is below amaximum predetermined temperature, sufficient to cool the charge air forthe engine 102 in the after-cooler 122. Similarly, the second auxiliarythermostat 130 may ensure that the coolant supplied from the engine 102to the pump 114 is again below a maximum predetermined temperature to besupplied to the second circuit 112 after mixing in the pump 114.

Consequently, the cooling arrangement 108 of the present disclosure withthe triple thermostat configuration, in addition to regulating the flowof the coolant between the first and second circuits 110, 112, mayenable the cooling arrangement 108 to work with a single pump 114. Thisis primarily made possible, as the thermostats 126, 128, 130 mayregulate the flow of the coolant through the pump 114, for circulationof the coolant in both the first and the second circuits 110, 112 withvarying temperature ranges, ensuring that the temperature of the coolantlies within a safe operating temperature range of the pump 114.

Further, the orifice 134 disposed in the bypass line 132 may act tocontrol the flow rate of the coolant through the bypass line 132. Thediameter of the orifice 134 may be calculated based on thespecifications of the thermostat 126 and the needed flow rate throughthe bypass line 132, as determined to compensate for the transient loadrequirements of the engine 102. In an embodiment, the coolingarrangement 108 may include a variable orifice 134 for the bypass line132.

In addition to controlling the flow rate of the coolant through thebypass line 132, the orifice 134 may also help in raising thetemperature of the coolant flowing from the first circuit 110 to thesecond circuit 112. As the flow of the coolant may be restricted by theorifice 134, there may be a drop in velocity of the flow of the coolant.This may lead to the coolant in the bypass line 132, typically disposednear the after-cooler 122, to absorb some of the heat from the chargeair at higher temperature in the after-cooler 122, as the coolantremains in close proximity to the after-cooler 122 for longer duration.

Thus, the cooling arrangement 108 of the present disclosure, with thethermostat 126 and the bypass line 132 including the orifice 134, mayhelp to provide a constant bleed of the coolant and control the flowrate of the coolant between the first and the second circuits 110, 112.Thus, the cooling arrangement 108 may achieve the needed responsivenessto address the transient loading of the engine 102, thereby improvingthe efficiency of the marine power system 100, in general.

Although the embodiments of this disclosure as described herein may beincorporated without departing from the scope of the following claims,it will be apparent to those skilled in the art that variousmodifications and variations can be made. Other embodiments will beapparent to those skilled in the art from consideration of thespecification and practice of the disclosure. It is intended that thespecification and examples be considered as exemplary only, with a truescope being indicated by the following claims and their equivalents.

What is claimed is:
 1. A cooling arrangement comprising: a firstcircuit; a second circuit configured to be in fluid communication withthe first circuit; a coolant for circulating in the first circuit andthe second circuit; a pump configured to receive the coolant from thefirst circuit and the second circuit, the pump further configured tocirculate the coolant back to the first circuit and the second circuit;an after-cooler disposed in the first circuit of the coolingarrangement; a thermostat disposed in connection with the after-coolerin the first circuit, the thermostat is configured to regulate the flowof the coolant from the after-cooler to the pump based on thetemperature of the coolant from the after-cooler; and a bypass linedisposed in the first circuit parallel to the thermostat, the bypassline is configured to provide a constant bleed of the coolant in thecooling arrangement.
 2. The cooling arrangement of claim 1, wherein thefirst circuit further includes a first auxiliary thermostat configuredto regulate the flow of the coolant from the pump to the first circuit.3. The cooling arrangement of claim 1, wherein the second circuitfurther includes a second auxiliary thermostat configured to regulatethe flow of coolant from the second circuit to the pump.
 4. The coolingarrangement of claim 1, wherein the first circuit is a low temperaturecircuit further including an after-cooler heat exchanger in connectionwith the after-cooler, the after-cooler heat exchanger configured tocool the coolant supplied to the after-cooler from the pump.
 5. Thecooling arrangement of claim 1, wherein the second circuit is a hightemperature circuit in connection with an engine, the second circuitfurther includes a heat exchanger configured to cool the coolantsupplied to the pump from the engine.
 6. The cooling arrangement ofclaim 5, wherein the second circuit further includes a turbochargerconfigured to provide a charge air to the engine via the after-cooler.7. The cooling arrangement of claim 1, wherein the bypass line furtherincludes an orifice disposed within, the orifice is configured tocontrol the flow of the coolant through the bypass line based on thediameter of the orifice.
 8. The cooling arrangement of claim 7, whereinthe orifice has the diameter of approximately 2-12 millimeters.
 9. Thecooling arrangement of claim 7, wherein the orifice has the diameter ofapproximately 5 millimeters.
 10. A marine power system comprising: anengine; and a cooling arrangement configured to extract heat from theengine by a coolant, the cooling arrangement including: an after-coolerconfigured to cool a charge air for the engine by the coolant, a pumpconfigured to receive the coolant from the after-cooler and the engine,and re-circulates the coolant back to the after-cooler and the engine, athermostat disposed in connection with the after-cooler, the thermostatis configured to regulate a flow of the coolant from the after-cooler tothe pump based on the temperature of the coolant from the after-cooler,a bypass line disposed in parallel to the thermostat, the bypass line isconfigured to provide a constant bleed of the coolant in the coolingarrangement, and an orifice disposed in the bypass line to control theflow of the coolant through the bypass line.
 11. The marine power systemof claim 10 further includes a turbocharger configured to provide thecharge air to the engine via the after-cooler.
 12. The marine powersystem of claim 10 further includes a heat exchanger configured to coolthe coolant from the engine.
 13. The marine power system of claim 10further includes a first auxiliary thermostat configured to regulate theflow of coolant from the pump to the after-cooler.
 14. The marine powersystem of claim 10 further includes a second auxiliary thermostatconfigured to regulate the flow of coolant from the engine to the pump.15. The marine power system of claim 10, wherein the orifice isconfigured to control the flow of the coolant through the bypass linebased on the diameter of the orifice.
 16. The marine power system ofclaim 15, wherein the orifice has the diameter of approximately 2-12millimeters.
 17. The marine power system of claim 15, wherein theorifice has the diameter of approximately 5 millimeters.
 18. A methodfor cooling an engine, the method comprising: receiving a coolant fromthe engine to a pump; pumping the coolant from the pump to anafter-cooler; regulating the flow of the coolant from the after-coolerto the pump, to be supplied back to the engine, by a thermostat; andproviding a bypass line in parallel to the thermostat to provide aconstant bleed of the coolant from the after-cooler to the engine. 19.The method of claim 18, wherein regulating the flow of the coolantfurther includes allowing the coolant to flow through the thermostatbased on the temperature of the coolant from the after-cooler.
 20. Themethod of claim 18, wherein providing the bypass line further includesdisposing an orifice within the bypass line to control the flow of thecoolant through the bypass line.